There have been clashes between environmental protestors and police in northern Germany at the proposed location of a new coal-fired power-station.
Up to 700 demonstrators turned up at the site at Moorburg, a suburb of Hamburg.
The campaigners argue that should the plant go ahead, emissions of carbon dioxide would increase by 40 per cent in the Hamburg area.
The power giant Vattenfall has promised to install technology at Moorburg to capture the greenhouse gas by 2013, but opponents point to the fact that there are also 25 other coal-fired power-plants in the pipeline in Germany.
Environmentalists say coal-burners produce around twice as much CO2 as gas-fired generators. But the country has a plentiful domestic supply of the dirtiest type of coal, lignite, reducing the need for energy imports.
Germany and other EU states have agreed to cut CO2 emissions by a fifth by the year 2020.